SDLG WP6, Руководство по обслуживанию

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Service Manual for WP6 Diesel Engine
32
Reference table for valve recession requirements:
Required value of valve recession (mm)
Intake valve 1.0~1.45
Exhaust valve 1.0~1.45
If valve recession exceeds allowed range, the cylinder cover must be replaced to ensure reliability
of diesel engine. If valve recession doesn’t exceed allowed range, disassemble the valve to check
the sealing surface between valve and valve seat for obvious wear and abnormal damage.
(3) Clearance between valve rod and valve guide pipe
Internal surface of valve guide pipe is the contacting surface between valve rod and valve guide
pipe, if clearance between valve rod and valve guide pipe exceeds allowed value due to abrasion,
then the guide effect will at state, which may affect reliability of the engine. The inner diameter of
guide pipe can be measured with an inside micrometer, as shown in Fig. 3-5. Outer diameter of
valve rod can be measured with an outside micrometer. Both allowed ranges for clearance between
intake valve rod and its guide pipe, exhaust valve rod and its guide pipe are 0.03~0.06mm. If
clearance exceeds allowed range, the cylinder cover must be replaced to ensure reliability of diesel
engine.
Fig. 3-5
(4) Cylinder cover gasket
If there is air leakage, water leakage or oil leakage in cylinder cover gasket, then the gasket should
be checked and replaced;
Check the gasket for visible damage and analyze the cause, cylinder cover gaskets are disposable,
and should be replaced during maintenance.
3234 Steps to Assemble Cylinder Cover
(1) Preassemble intake and exhaust valve module;
(2) Install cylinder cover gaskets, thickness of cylinder cover gasket should be 1.4mm, and the
cylinder cover gasket cannot be reused.
(3) Assemble the cylinder cover to engine block;
(4) Loose-fit cylinder cover bolts;
(5) Fasten cylinder cover bolts, firstly pre-tighten each bolt to 30Nm, and then tighten each bolt for